Objective: The aim of the present study was to elucidate whether occupational exposure to vapors, gases, dusts, and fumes increases the mortality risk of COPD, especially among never smokers.
Methods: The study population was a cohort of 354,718 male construction workers; of these, 196,329 were exposed to vapors, gases, dusts, and fumes, and 117,964 were unexposed. Exposure to inorganic dust, wood dust, vapors, fumes, gases, and irritants was based on a job-exposure matrix with a focus on exposure in the mid-1970s. The cohort was followed from 1971 to 2011. Relative risks (RRs) were obtained using Poisson regression models adjusting for age, BMI, and smoking habits.
Results: There were 1,085 deaths from COPD among the exposed workers, including 49 never smokers. Workers with any occupational exposure to vapors, gases, fumes, and dust showed an increased mortality due to COPD (RR, 1.32; 95% CI, 1.18-1.47). When comparing different exposure groups, there was a significantly increased mortality due to COPD among those exposed to fumes (RR, 1.20; 95% CI, 1.07-1.36) and inorganic dust (RR, 1.19; 95% CI ,1.07-1.33). Among never smokers, there was high mortality due to COPD among workers with any occupational airborne exposure (RR, 2.11; 95% CI, 1.17-3.83). The fraction of COPD attributable to occupational exposure was 0.24 among all workers and 0.53 among never-smoking workers.
Conclusions: Occupational exposure to airborne pollution increases the mortality risk for COPD, especially among never smokers.